Well…I don’t think there is any physiologic difference between what you call MAF and what you cal AeT.
I think of VT1 as ‘first ventilatory threshold’…the point where there is some nominally observable increase in blood lactate. Most riders will be able to sustain VT1 for WAY more than 60 to 120 minutes. If you are riding at a pace you can only sustain for an hour…that’s something physiologically different from VT1.
If I understand you correctly, you’re trying to narrow down a training zone to something less than a 10 bpm band. Even if such a training zone did exist it would be very difficult to maintain during any practical training session. So…you know…don’t spend too much time thinking about it is my advice.